Semion Mosheshvili, 42, was handling the gun in the upstairs bedroom of the house on Deisius St. near Prall Ave. in Huguenot Saturday night when he accidentally squeezed off a round, his lawyer, Arthur Gershfeld, told the Daily News.

“He had no idea the gun was loaded and there is no question this was an accident,” Gershfeld said. “Everybody knows it was an accident. Even the police.”

The bullet tore through three walls and a ceiling before lodging into the shoulder of the boy, who was playing in the kitchen downstairs, Gershfeld said. He was taken to Staten Island University Hospital where he was in stable condition Sunday.